1186384-06-4Relevant academic research and scientific papers
Practical and highly selective sulfur ylide-mediated asymmetric epoxidations and aziridinations using a cheap and readily available chiral sulfide: Extensive studies to map out scope, limitations, and rationalization of diastereo- and enantioselectivities
Illa, Ona,Namutebi, Mariam,Saha, Chandreyee,Ostovar, Mehrnoosh,Chen, C. Chun,Haddow, Mairi F.,Nocquet-Thibault, Sophie,Lusi, Matteo,McGarrigle, Eoghan M.,Aggarwal, Varinder K.
supporting information, p. 11951 - 11966 (2013/09/02)
The chiral sulfide, isothiocineole, has been synthesized in one step from elemental sulfur, γ-terpinene, and limonene in 61% yield. A mechanism involving radical intermediates for this reaction is proposed based on experimental evidence. The application of isothiocineole to the asymmetric epoxidation of aldehydes and the aziridination of imines is described. Excellent enantioselectivities and diastereoselectivities have been obtained over a wide range of aromatic, aliphatic, and α,β-unsaturated aldehydes using simple protocols. In aziridinations, excellent enantioselectivities and good diastereoselectivities were obtained for a wide range of imines. Mechanistic models have been put forward to rationalize the high selectivities observed, which should enable the sulfide to be used with confidence in synthesis. In epoxidations, the degree of reversibility in betaine formation dominates both the diastereoselectivity and the enantioselectivity. Appropriate tuning of reaction conditions based on understanding the reaction mechanism enables high selectivities to be obtained in most cases. In aziridinations, betaine formation is nonreversible with semistabilized ylides and diastereoselectivities are determined in the betaine forming step and are more variable as a result.
Stereospecific ring expansion of chiral vinyl aziridines
Brichacek, Matthew,Navarro Villalobos, Mauricio,Plichta, Alexandra,Njardarson, Jon T.
, p. 1110 - 1113 (2011/04/25)
In this report, it is demonstrated that chiral vinyl aziridines can be stereospecifically ring expanded. This synthetic approach allows controlled access to chiral 2,5-cis-or 2,5-trans-3-pyrroline products from starting materials with the appropriate aziridine geometry. Twenty three ring expansion examples, most of which feature a stereospecific cyclization, are presented.(Figure Presented)
Palladium-mediated annulation of vinyl aziridines with michael acceptors: Stereocontrolled synthesis of substituted pyrrolidines and its application in a formal synthesis of (-)-α-kainic acid
Lowe, Martin A.,Ostovar, Mehrnoosh,Ferrini, Serena,Chen, C. Chun,Lawrence, Paul G.,Fontana, Francesco,Calabrese, Andrew A.,Aggarwal, Varinder K.
supporting information; experimental part, p. 6370 - 6374 (2011/09/12)
Just add salt: Vinyl aziridines have been treated with methyl vinyl ketone or ethyl thioacrylate in the presence of Pd0 to give pyrrolidines with moderate to good diastereoselectivity. The presence of nBu4NCl was critical to successf
